Car exhaust and other urban fumes can disrupt moths’ ability to make their way to flowers, a new
study reports.

“The flowers occur in patches that can be (miles) away, and these moths are almost at the edge
of survival trying to find them,” said Jeff Riffell, a biologist at the University of Washington
and the first author of the study, which appears in the journal
Science.

The research focuses on the tobacco hornworm moth, which depends on nectar for energy.

The scientists sampled flower scents and other odors with a sensitive mass spectrometer, and
then used a wind tunnel to determine how different combinations of smells affected a moth’s ability
to find flowers. They found that the moths did far better in rural environments than in urban and
suburban ones.

But it is not just man-made odors that affect the moths. Scents from neighboring vegetation can
be very disruptive as well, Riffell said.

Disco clam’s secret: mirror balls on its lip

Ctenoides ales is well known to scuba divers, who call it the disco clam for its
mirror-ball luminescence. But few scientists had given it much notice.

Now, in the
Journal of the Royal Society Interface, researchers report that they have discovered the
mechanism that gives the clam its flash.

The inside of the clam’s lip, it turns out, is full of nanospheres of light-reflecting silica;
by contrast, the outside of the lip has no silica and is highly light-absorbent.

“So it furls and unfurls, creating two flashes per second,” said Lindsey Dougherty, a doctoral
student at the University of California-Berkeley.

When she presented the clams with artificial predators in the lab, she saw an increase to four
flashes per second. The inside lip is particularly good at reflecting blue light — perfect for the
ocean.